spi: microchip-core: Use helper function devm_clk_get_enabled()

Since commit 7ef9651e9792 ("clk: Provide new devm_clk helpers for prepared
and enabled clocks"), devm_clk_get() and clk_prepare_enable() can now be
replaced by devm_clk_get_enabled() when driver enables (and possibly
prepares) the clocks for the whole lifetime of the device. Moreover, it is
no longer necessary to unprepare and disable the clocks explicitly.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Link: https://lore.kernel.org/r/20230823133938.1359106-19-lizetao1@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: switch to use modern name

Change legacy name master/slave to modern name host/target or controller.

No functional changed.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20230823033003.3407403-7-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: Clean up redundant dev_err_probe()

Refering to platform_get_irq()'s definition, the return value has
already been checked if ret < 0, and printed via dev_err_probe().
Calling dev_err_probe() one more time outside platform_get_irq()
is obviously redundant.

Furthermore, platform_get_irq() will never return irq equals 0,
removing spi->irq == 0 checking to clean it up.

Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230728075729.3451867-1-chenjiahao16@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: Replace all spi->chip_select and spi->cs_gpiod references with function call

Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod
members of struct spi_device to be an array. But changing the type of these
members to array would break the spi driver functionality. To make the
transition smoother introduced four new APIs to get/set the
spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and
spi->cs_gpiod references with get or set API calls.
While adding multi-cs support in further patches the chip_select & cs_gpiod
members of the spi_device structure would be converted to arrays & the
"idx" parameter of the APIs would be used as array index i.e.,
spi->chip_select[idx] & spi->cs_gpiod[idx] respectively.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>
Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers
Reviewed-by: Michal Simek <michal.simek@amd.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver
Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi
Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver
Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part
Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230303172041.2103336-38-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: Remove the unused function mchp_corespi_enable()

The function mchp_corespi_enable() is defined in the spi-microchip-core.c
file, but not called elsewhere, so delete this unused function.

drivers/spi/spi-microchip-core.c:122:20: warning: unused function 'mchp_corespi_enable'.

Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=2418
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20221017092141.9789-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: Simplify some error message

dev_err_probe() already prints the error code in a human readable way, so
there is no need to duplicate it as a numerical value at the end of the
message.

Moreover, in the case of devm_clk_get() it would only display '0' because
'ret' is know to be 0 at this point.

Fixes: cdeaf3a99a02 ("spi: microchip-core: switch to use dev_err_probe()")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/fb894ecec68e03fb7fc9353027c8b1a2610833d7.1659735153.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: switch to use dev_err_probe()

Switch to use dev_err_probe() to simpify error path.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-4-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: switch to use devm_spi_alloc_master()

Switch to use devm_spi_alloc_master() to simpify error path.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-3-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: fix UAF in mchp_corespi_remove()

When using devm_spi_register_master(), the unregister function will
be called in devres_release_all() which is called after ->remove(),
so remove spi_unregister_master() andspi_master_put().

Fixes: 9ac8d17694b6 ("spi: add support for microchip fpga spi controllers")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220713025657.3524506-2-yangyingliang@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: fix passing zero to PTR_ERR warning

It is possible that the error case for devm_clk_get() returns NULL,
in which case zero will be passed to PTR_ERR() as shown by the Smatch
static checker warning:
drivers/spi/spi-microchip-core.c:557 mchp_corespi_probe()
warn: passing zero to 'PTR_ERR'

Remove the NULL check and carry on with a dummy clock in case of an
error. To avoid a potential div zero, abort calculating clkgen if
clk_get_rate(spi->clk) is zero.

Fixes: 9ac8d17694b6 ("spi: add support for microchip fpga spi controllers")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/linux-spi/20220615091633.GI2168@kadam/
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220615142028.2991915-1-conor.dooley@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: microchip-core: fix potentially incorrect return from probe

If platform_get_irqi() returns 0, the error case will be triggered but
probe() will return 0 rather than an error. Ape the other drivers using
this pattern and return -ENXIO.

Reported-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/linux-spi/20220609055533.95866-2-yang.lee@linux.alibaba.com/
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Fixes: 9ac8d17694b6 ("spi: add support for microchip fpga spi controllers")
Link: https://lore.kernel.org/r/20220614065809.1969177-1-conor.dooley@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: micro: fix unreasonable clk_prepare_enable() on error in mchp_corespi_probe()

Fix the unreasonable clk_prepare_enable() with clk_disable_unprepare()
before return from mchp_corespi_probe() in the error handling case.

Signed-off-by: Peng Wu <wupeng58@huawei.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220611021117.40494-1-wupeng58@huawei.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: fix platform_no_drv_owner.cocci warning

Remove .owner field if calls are used which set it automatically.

Eliminate the following coccicheck warning:
./drivers/spi/spi-microchip-core.c:624:3-8: No need to set .owner here.
The core will do it.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220609055533.95866-1-yang.lee@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>

spi: add support for microchip fpga spi controllers

Add a driver for Microchip FPGA SPI controllers, specifically
supporting the "hard" controllers on PolarFire SoC.

Co-developed-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220607073833.2331539-2-conor.dooley@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>